//The number of expansions without repetition D2

#include <stdio.h>

double q(int n,int k);
double a[500][500]={0.0};

int main()
{
	int N=0;
	if(scanf("%d",&N)!=1||1>N||N>=500) return printf("ERROR\n"),1;
	printf("%1.0f\n",q(N,N));
	return 0;
}

double q(int n,int k)
{

	if (k>0&&(n==1||n==0)) return 1.0;
	if (k>n) return q(n,n);
	if (k<=1) return 0;
	if (a[n][k]) return a[n][k];
	else a[n][k]=q(n-k,k-1)+q(n,k-1);
	return a[n][k];
}
